To Legion:
I don't see any reason at all to launch an attack before the second caravan leaves. They don't have the item and simply add to the foes. Personally, I see two options:
1. Attack after the first group leaves. That sword seems really valuable and like something we don't want them to have. Of course, that isn't the quest either.
2. Don't attack. Even better, if they are headed to the fortress we now have an unwitting guide to take us to where we want to go. Just follow quietly along.
As much as I would like to get that sword, I think it probably makes the most sense to follow them. My one argument against that really is that given the spooky nature of this meadow it would be fun to try and spook some orcs. I suppose we could do that even if we do just follow them. Thoughts?